US Supreme Court lets Trump administration turn away asylum seekers at Mexico border

The United States Supreme Court has cleared the way for President Donald Trump’s administration to turn away asylum seekers before they physically enter the United States, delivering a major victory for the White House’s immigration enforcement strategy. In a 6 to 3 ruling issued on June 25, 2026, the court held that a person standing on the Mexican side of the border has not legally “arrived in the United States” for the purposes of federal asylum and inspection laws. The decision overturns a lower-court ruling that had found the border practice known as metering unlawful. The Trump administration may now revive metering when ports of entry are considered too congested to process additional claims, although no detailed implementation timetable had been announced by June 26.

The decision in Mullin v. Al Otro Lado does not abolish the United States asylum system or prevent every person entering the country from requesting protection. It allows United States Customs and Border Protection officers to restrict access before an applicant crosses the international boundary, potentially keeping people in Mexico without beginning the formal asylum process. The ruling also remains distinct from the Trump administration’s broader attempt to suspend asylum access for many people entering through the southern border, which is being challenged separately.

The judgment creates immediate operational authority for the executive branch and a wider legal precedent about where statutory asylum protections begin. For migrants fleeing persecution, the physical border line may now determine whether an immigration officer must inspect them and consider an asylum request. For the United States government, the decision restores a border-management mechanism first introduced during the administration of President Barack Obama and expanded during President Donald Trump’s first term.

What did the United States Supreme Court decide in Mullin v. Al Otro Lado?

The case centred on two provisions of the Immigration and Nationality Act governing asylum applications and the inspection of people seeking admission. Federal law states that a non-citizen who arrives in the United States may apply for asylum and must be inspected by an immigration officer. The dispute concerned whether someone who reaches an official border crossing but is stopped while still physically in Mexico has arrived in the United States within the meaning of those provisions.

Associate Justice Samuel Alito wrote the majority opinion and concluded that the statutory wording requires actual entry into United States territory. The majority reasoned that, in ordinary language, a person arrives in a country only after crossing its border rather than upon approaching it or requesting permission to enter. Chief Justice John Roberts and Associate Justices Clarence Thomas, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett joined the majority.

The ruling reversed the United States Court of Appeals for the Ninth Circuit, which had concluded in 2024 that border officers were legally required to inspect asylum seekers presenting themselves at designated ports of entry, including those stopped immediately before entering the country. The appellate court had determined that metering unlawfully withheld access to mandatory inspection and asylum procedures.

The Supreme Court’s decision does not require the Trump administration to meter asylum claims. It gives the Department of Homeland Security discretion to resume the practice if officials determine that changing border conditions, processing limitations or congestion justify its use. The government had previously indicated that it considered metering an important border-management tool and could restore it when circumstances warranted.

How does the metering policy prevent migrants from beginning the asylum process?

Metering allows border officers to limit the number of people permitted to enter a port of entry for inspection during a particular period. When officials conclude that a crossing has reached its processing capacity, asylum seekers waiting in Mexico can be told to return later rather than being admitted for screening.

Once a person enters the United States and expresses an intention to apply for asylum or a fear of persecution, federal law establishes procedures for inspection and further assessment. The person may undergo an initial screening to determine whether there is a credible fear of persecution or torture. Metering intervenes before those procedures begin by preventing the person from crossing the border and entering the statutory process.

The practice emerged at one southern-border crossing in 2016 amid an increase in people seeking admission. It expanded into a more formal policy during President Donald Trump’s first administration in 2018, when officers were authorised to delay processing if the government considered a port unable to handle additional applicants. President Joe Biden’s administration rescinded the policy in 2021.

In some locations, waiting systems developed to manage the order in which applicants might eventually be admitted. These systems included handwritten lists and records maintained with participation from Mexican officials or local organisations. Applicants could remain in Mexican border communities for extended periods without a guaranteed date for entering the United States.

The legal effect of the June 25 decision is that federal asylum law does not require United States officials to process every person approaching a port while that person remains outside national territory. The operational effect will depend on how widely and consistently the Department of Homeland Security uses the restored authority.

Why did the three dissenting justices say the ruling undermines the asylum system?

Associate Justice Sonia Sotomayor wrote the dissenting opinion, joined by Associate Justices Elena Kagan and Ketanji Brown Jackson. The dissent argued that the majority had placed excessive weight on the word “in” while failing to read the statute as a complete framework governing people arriving at official ports and seeking admission.

Associate Justice Sonia Sotomayor maintained that Congress had created mandatory inspection procedures for non-citizens presenting themselves at the border. Under that interpretation, federal officers could not avoid those obligations by standing at the territorial boundary and physically preventing applicants from taking the final step into the United States.

The dissent warned that the ruling would leave some people exposed to persecution, criminal violence or dangerous journeys while they searched for another port willing to process them. Associate Justice Sonia Sotomayor also argued that restricting lawful access could encourage applicants to attempt unauthorised crossings through deserts, rivers or other hazardous terrain.

The disagreement between the majority and dissent was therefore not about whether the United States may regulate admission. It concerned where the government’s statutory duties begin. The majority located that point after physical entry, while the dissent treated arrival at an official threshold and a request for admission as sufficient to trigger inspection.

The strength of the disagreement was reflected inside the courtroom. Associate Justice Samuel Alito read a summary of the majority judgment from the bench, while Associate Justice Sonia Sotomayor delivered an extended summary of the dissent. Reading a dissent from the bench is generally associated with particularly strong disagreement over a decision’s reasoning or consequences.

How could the ruling change conditions for asylum seekers waiting in northern Mexico?

The immediate humanitarian consequences will depend on the number of ports applying metering, the daily processing limits and the length of time applicants are asked to wait. A narrowly used system responding to short-term congestion would produce different effects from a broad policy that regularly prevents most asylum seekers from entering.

Migrants waiting in northern Mexico may face unstable housing, limited employment, insufficient medical care and exposure to criminal organisations. Families can also encounter difficulty maintaining documentation, attending appointments and obtaining reliable information about when a port may begin accepting additional applicants.

A prolonged waiting system could shift more responsibility towards Mexico. Mexican federal and local authorities, shelters and humanitarian groups may be required to accommodate people who have reached the United States border but cannot access its asylum system. This could place additional pressure on cities such as Tijuana, Ciudad Juárez, Matamoros and Reynosa.

The decision could also influence migration routes. Some applicants may wait at official ports, while others may attempt to enter between crossings so that they are physically present in the United States and can request protection. The dissent identified that possibility as a foreseeable consequence of restricting access at official entry points.

The Trump administration argues that metering provides an orderly response when border facilities cannot safely process everyone arriving at once. The Department of Homeland Security has presented the ruling as confirmation that a person remains outside the United States until the border is physically crossed and that the government may manage entry accordingly.

Does the ruling eliminate the right to seek asylum under United States law?

The Supreme Court did not invalidate the federal asylum statute or hold that all asylum seekers can be rejected without assessment. People who are physically present in the United States remain able to invoke asylum provisions, subject to eligibility restrictions, procedural rules and other Trump administration policies.

The judgment is instead about territorial access to the asylum process. It allows officials to prevent a person waiting outside the United States from reaching the location where statutory inspection and asylum rights become enforceable under the majority’s interpretation.

This creates a significant practical limitation even though the formal right continues to exist. A legal protection may be difficult to use when the government can prevent the intended beneficiary from reaching the point at which that protection applies.

The decision also does not resolve the legality of the Trump administration’s separate policy seeking to restrict asylum more broadly at the southern border. That measure involves different executive actions and legal arguments. Courts examining those challenges may consider statutory asylum rights, presidential authority, immigration law and international protection obligations independently of the metering ruling.

Applicants admitted for inspection will still need to establish eligibility. Asylum is not automatically granted when a person enters the process. Applicants generally must demonstrate persecution or a well-founded fear of persecution connected to protected grounds, while other restrictions can disqualify or limit a claim.

Why is the Supreme Court ruling a wider victory for Donald Trump’s executive authority?

The ruling gives the Trump administration greater discretion over access to the asylum system without requiring Congress to amend the Immigration and Nationality Act. It also overturns a judicial interpretation that had imposed a mandatory processing obligation at the international boundary.

The decision arrived on the same day that the Supreme Court issued another 6 to 3 immigration ruling allowing the administration to terminate Temporary Protected Status for more than 350,000 Haitians and approximately 6,100 Syrians. In that case, the majority held that the relevant statute largely prevented courts from reviewing executive determinations concerning the designation, termination or extension of Temporary Protected Status.

Together, the decisions strengthen presidential control over two different humanitarian pathways. Metering concerns whether asylum seekers outside the country can begin applying for protection. Temporary Protected Status concerns whether designated nationals already living in the United States may continue receiving temporary protection from deportation.

The outcomes do not give the executive branch unlimited immigration authority. Courts can still review constitutional claims and statutory questions where Congress has permitted judicial review. The Supreme Court has also ruled against President Donald Trump in other disputes, demonstrating that the court’s conservative majority does not automatically accept every assertion of executive power.

However, the June 25 rulings show considerable judicial deference where immigration law grants discretion to the executive branch or where the statutory language can be read as restricting court intervention. That pattern may shape other cases involving removals, humanitarian programmes and border enforcement.

What happens next at the United States and Mexico border after the ruling?

United States Secretary of Homeland Security Markwayne Mullin must now decide whether, where and under what conditions metering will resume. Markwayne Mullin became the ninth Secretary of Homeland Security in March 2026 and is the named government official in the Supreme Court case.

The Department of Homeland Security could issue operational instructions defining when a port is considered overburdened, how many applicants can be processed and how people waiting outside the United States will receive information. Those details will determine whether metering functions as a temporary capacity measure or a sustained barrier to asylum access.

New litigation remains possible if implementation raises separate constitutional or statutory issues not resolved in Mullin v. Al Otro Lado. Legal organisations may challenge discriminatory application, indefinite waiting, the treatment of children or other operational practices. The Supreme Court’s interpretation of arrival will nevertheless make it more difficult to argue that federal asylum-processing duties apply before physical entry.

Mexico’s response will also matter. A large waiting population would require coordination involving security, shelters, local government and humanitarian organisations. Mexican authorities may resist arrangements that leave applicants indefinitely stranded inside Mexican territory without a functioning admission process.

The judgment settles the principal legal question before the court, but it does not settle the political argument. Supporters view the ruling as recognition that governments must control entry and manage finite processing capacity. Opponents see it as permission to prevent people fleeing persecution from reaching a legal protection that Congress intended them to use.

What are the key takeaways from the Supreme Court ruling on border asylum processing?

• The United States Supreme Court ruled by six votes to three on June 25, 2026, that asylum seekers standing in Mexico have not legally arrived in the United States until they physically cross the international border.
• The decision allows President Donald Trump’s administration to revive metering, a policy under which border officers may limit asylum processing and tell applicants waiting outside congested ports of entry to return later.
• Associate Justice Samuel Alito wrote the majority opinion, joined by Chief Justice John Roberts and Associate Justices Clarence Thomas, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett.
• Associate Justice Sonia Sotomayor, joined by Associate Justices Elena Kagan and Ketanji Brown Jackson, argued that Congress required immigration officers to inspect people presenting themselves at official ports and seeking admission.
• The metering practice began during President Barack Obama’s administration in 2016, expanded during President Donald Trump’s first term and was formally rescinded by President Joe Biden’s administration in 2021.
• The ruling does not abolish asylum or decide the legality of every Trump administration border restriction, but it limits access by allowing officials to stop applicants before statutory asylum procedures begin.
• The Department of Homeland Security had not announced a detailed timetable by June 26 for restoring metering, leaving important questions about processing limits, waiting systems and affected ports unresolved.
• The decision came alongside another 6 to 3 ruling allowing the administration to terminate Temporary Protected Status for more than 350,000 Haitians and approximately 6,100 Syrians living in the United States.